Technological advances in computer hardware, software and networking have lead to efficient, cost effective computing systems (e.g., desktop computers, laptops, handhelds, cell phones, servers . . . ) that can communicate with each other from essentially anywhere in the world in order to exchange information. These systems continue to evolve into more reliable, robust and user-friendly systems. As a consequence, more and more industries and consumers are purchasing computers and utilizing them as viable electronic alternatives to traditional paper and verbal media for exchanging information. For example, many industries and consumers are leveraging computing technology to improve efficiency and decrease cost through web-based (e.g., on-line) services. For instance, consumers can search and retrieve particular information (e.g., via a search engine), purchase goods, view bank statements, invoke monetary transactions (e.g., pay a bill on-line), research products and companies, apply for employment, obtain real-time stock quotes, obtain a college degree, download files and applications, transmit correspondence (e.g., email, chat rooms . . . ), etc. with the click of a mouse.
In many instances, a search engine is utilized to search for information. In general, a search engine is a special program (e.g., computer executable instructions) designed to help find files (e.g., web pages, images, text . . . ) stored on a computer, for example, a public server or on one's own personal computer. A typical search engine allows a user to invoke a query for files that satisfy particular criteria, for example, files that contain a given word or phrase in a title or body. Web search engines generally work by storing information about a large number of web pages retrieved from the World Wide Web (WWW) through a web crawler, or an automated web browser, which follows essentially every link it locates. The contents of each web page are then analyzed to determine how it should be indexed, for example, words can be extracted from the titles, headings, or special fields called meta-tags. Data about web pages is stored in an index database for use in later queries. Some search engines store (or cache) all or part of a source page as well as information about the web pages. When a user invokes a query through the web search engine by providing key words, the web search engine looks up the index and provides a listing of web pages that best-match the criteria, usually with a short summary containing the document's title and/or parts of the text. Some web search engines employ a real-time approach, wherein information is obtained when a query is started rather than obtaining stored information through indexing. With this approach, the information is more up-to-date and there typically are less dead links and less system resources are needed, but more time is generally required to complete the request.
In general, the usefulness of a search engine depends on the relevance of the results it presents to a user and the presentation of such results. While there can be numerous web pages that include a particular word or phrase, some web pages may be more relevant, popular, or authoritative than others. Most search engines employ methods to rank the results to provide a“best” result first. How a search engine decides which pages are the best matches, and what order the results should be shown in, varies widely from one engine to another. A page is ranked based on how well it fits the user's query in combination of a query independent rank of the page. The query independent rank can be based on a multitude of factors such as the number of incoming links, the site traffic, how long the site has been around or the PageRank of the page. Techniques which utilize the link structure of a graph (e.g., PageRank) usually make the incorrect assumption that all hyperlinks should be treated equally. In reality this is not true; a page links to many places because they include ads and navigational links which may not be important. In fact there are many links on a page that are never followed, and sometimes there are few links which get a majority of the click-throughs. Plus, many pages are just pages to pass through to get to another more important page.